Process of preparing z



Patented Jan. 19, 1932 UNITED, STATES WINIERIID HENTRICHQ OF WIESDORF-ON-THE-RHINE, AND, J'OSEIE HILGER, QF COLOGNE- MULHEIM, GERMANY, ASSIGNORS TO GENERAL ANILINE WORKS, INCL, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE g rnocn'ss or PREPARING 2:4-IDI-NITROPHENYL-G-HYDROXYTRIAZINE-l a 5 No Drawing. Application filed September 23, 1929, Serial No. 394,728, and in Germany October 31, 1928.

The present invention relates to the manufacture of 2: 4- di- (nitrophenyl) -6-hydr0xytriazine-l: 3: 5. V

The 2: 4-di- (-nitrophenyl) -6-hydroxytri- 5 azine-l: 3: 5

has been described by Rappeport (Ber. der deutschen Chemischen Gesellschaft, vol. 34, page 1989), and the 2: 4-di- (3'-nitrophenyl-) -6-hydroxytriazine-1: 3: 5 I by Pinner (Ber. der deutschen Chemischen Gesellschaft, vol. 28, page 482). Both authors obtainedthese compounds by the action of phosgene on the respective nitrobenzamidines. However, this process gives only a very inferior yield since a large quantity of amidine urea NH NH\ NOrOO 0 is produced, which in contradistinction to the non-nitrated product cannot be converted to the triazine by heating. Furthermore the method pursued by Pinner with excellent The Imido Aether, Berlin 1892, page 263) to proceed via the urethane of the formula to thetria'zine cannot be adopted in the case of the nitro benzamidines on account of the difiicult solubility of the free nitro-benzamidine bases.

In accordance with the present invention the readily accessible 2:4-diphenyl-6- hydroxytriazine-l: 3: 5 (Pinner, Die Imidoather, pages 263, 265) can be converted into the 2:4c-di-(nitrophenyl) -6-hydroXytriazine-1:3:5 with good yield by treating same for a prolonged time, say several hours with a nitrating agent, for example with nitrating acid or with nitric acid in sulfuric acid solution, favorably at low yield in the case of benzamidine (Pinner,

temperatures, say between about 10 and +301C.. The compound tllllSObtfiiIlGddlOW- ever, possesses a higher melting point than stated by Pinner. Probably Pinners product was still contaminated with the amidine urea and Pinner did notsucceed in obtaining the pure triazine on account ofits difiicult solubility. 4

The 2 l-di- (nitrophenyl) 6 -hydroxytriazine-l: 3: 5 is intended to find application as an intermediate product in the manufacture of dyestufis and pharmaceutical products.

The invention is illustrated by the follow-- ing examples, but is not restricted thereto Emample 1.'249 parts by weight of 2: 4.- diphenyl-6-hydroxytriazine-1 :73 5, (melting point 283 C.) are suspended in 3000 parts by weight of monohydrate; the calculated quantity of 25% nitrating acid is slowly dropped in with stirring at 10 C. After standing for 12 hours at roomtemperature the nitrating mass is poured on to ice, whereby the 2A-di- (nitrophenyl) -6-hydroxytriazine-1 3 5 precipitates. It is filtered by suction, thoroughly washed with Water and the filter residue dissolved in hot dioxane. After careful addition of water until turbidity commences the 2: i-di- (nitrophenyl) -6-hydroxytriazine-l 3: 5 separates on cooling in small clusters of fine needles. The compound is insoluble in alcohol, ether and benzene, difiicultly soluble in hot pyridine and readily soluble in hot dioxane. Its melting point is not sharp at 280-281 C. The yield amounts to 75 of theory.

Analysis: Calculated for (liaHo sNs 53- H N 0- Found: 53.15, 2.85, 20.77

Example 2:24.9 parts by weight of 2': 4- diphenyl-6-hydroxytriazine-1 :3: 5 are dissolved in 500 parts by weight of hot acetic acid. The solution is cooled with brisk stirring to 15-20 C, whereby part of the triazine precipitates and at this temperature 7 16.5 parts by weight of nitric acid of specific gravity 1.450 are slowly dropped in. After stirring for 12 hours the liquid is diluted with four times its volume of water and filtered by suction. The 2: l-di- (nitrophenyl) -6- inc hydroxytriazine-l: 3: 5 is obtained from hot dioxane in the form of small needles, melting at 280 (3.; the yield is about of'the theoretical.

We claim 1. The process'which comprises treating 2: 4-diph'enyl-G-hydroxytriazine-1: 3 5 with a nitrating agent. 2. The processwhich comprises treating 2: 4E-diphenyl-G-hydroxytriazined 3 5 with a nitrating agent at a temperature between about -10and +30 C. for a prolonged time.

3. The process which comprises slowly introducing a calculated amount of nitrating acid into a suspension of 2 -diphenyl-G-hydroxytriazine-l: 3 5 in sulfuric acid monohydrate at about +10 C. and allowing the reaction mass to stand several hours at room temperature.

In testimony whereof we afiix our signatures.

WINFRID HENTRICH. [1 s] JOSEF HILGER. [L. s] 

